The members of this vocal quartet helped fuel the late-20th-century boom in medieval and Renaissance vocal music, with multiple recordings of the radiant music of Hildegard von Bingen (and other composers of her era). Later, the members of Anonymous 4 ventured forward into the catalogue of a cappella Americana and also performed select pieces of contemporary music (including an extended work by Pulitzer winner David Lang). Whether singing plainchant, polyphony or post-minimal music, the group's sound is gleaming and gorgeous.